The lowest-priced Silverado Hybrid, which is only available as a four-door Crew Cab, sells for $41,888, and has an EPA rating of 21 mpg combined. A conventional Silverado Crew Cab with a V8 engine with an EPA rating of 16 mpg combined can be had for $9,000 less, and requires just $750 more fuel each year for the average user.

The Two-Mode hybrid powertrain employed in the trucks was jointly developed with BMW, Mercedes-Benz and Chrysler. The three other partner companies have already discontinued using the technology.

GM product chief Mary Barra recently said the company will be focusing its future green efforts on plug-in hybrid and all-electric powertrains, but has not revealed any plans for the electrification of its large trucks.

Fuel economy ratings for the 2014 pickups have not been determined, but the conventional V6 and V8 engines used feature direct fuel injection, variable valve timing and cylinder deactivation technology aimed at delivering improved efficiency.